Re: [PATCH AUTOSEL 6.9 01/40] workqueue: Refactor worker ID formatting and make wq_worker_comm() use full ID string

[Jan Engelhardt]

On Tuesday 2024-07-09 18:18, Sasha Levin wrote:

>From: Tejun Heo <tj@xxxxxxxxxx>
>
>[ Upstream commit 2a1b02bcba78f8498ab00d6142e1238d85b01591 ]
>
>TASK_COMM_LEN is only 16 leading to badly truncated names for
>rescuers. For example, the rescuer for the inet_frag_wq workqueue becomes:
>
>  $ ps -ef | grep '[k]worker/R-inet'
>  root         483       2  0 Apr26 ?        00:00:00 [kworker/R-inet_]

* very old Linux: process names are fixed to 16 bytes
* Linux 6.something: we relaxed it for kthreads in principle, but
  oopsie-daisie forgot one case so it's still 16 bytes for that one case
* 2a1b02: now that one case also has length limit lifted

which for me makes this count as a feature rather than a bugfix,
and I would not add it to -stable.
There might even be a poor soul who tests for exact process names in one
obscure shell script of his… would not want to break his setup when going
6.9.8->6.9.9, only with 6.9.8->6.10.